Introduction: There are few studies investigating the role of neoangiogenesis in biological behavior of salivary gland tumors. CD105 expression has demonstrated greater accuracy for detecting new vessel formation compared with other pan-endothelial molecules. This study aimed to assess and compare intratumoral Micro-Vessel Density (MVD) through using immunohistochemichal expression of CD105 biomarker in Mucoepidermoid Carcinoma (MEC), Adenoid Cystic Carcinoma (AdCC) and Pleomorphic Adenoma (PA).

Materials and Methods: CD105 expression using Immunohistochemistry (IHC) was assessed in 20 cases of PA, 20 cases of AdCC, 20 cases of MEC, and 10 cases of normal salivary gland tissues. Positive intratumoral micro-vessels for CD105 expression were measured quantitatively for the assessment of Micro-Vessel Density (MVD) in each group. Groups differences in MVD was analyzed statistically using the Mann-Whitney U test and Kruskal-Wallis test. One-way ANOVA and post hoc Tukey test were also carried out. P values less than 0.05 were considered statistically significant.

Results: CD105 positive vessels were rarely seen in normal salivary gland tissue. Statistically significant differences in MVD were observed between the normal salivary gland tissue and AdCC and also MEC (P<0.017 and P<0.001, respectively). There was a statistically significant difference in MVD between PA and AdCC and also MEC (P<0.018 and P<0.001, respectively). MVD was higher in MEC in comparison with AdCC (P<0.002).

Conclusion: The results of the current study demonstrated higher neoangiogenesis in AdCC and MEC by measuring CD105 expression, which suggests a possible role for this phenomenon in aggressive behavior of these malignant salivary gland tumors.